1 /*
2 * Copyright 2018 Google Inc.
3 *
4 * Use of this source code is governed by a BSD-style license that can be
5 * found in the LICENSE file.
6 */
7
8 #include "SkSGText.h"
9
10 #include "SkCanvas.h"
11 #include "SkPaint.h"
12 #include "SkPath.h"
13 #include "SkTArray.h"
14 #include "SkTextBlob.h"
15 #include "SkTypeface.h"
16
17 namespace sksg {
18
Make(sk_sp<SkTypeface> tf,const SkString & text)19 sk_sp<Text> Text::Make(sk_sp<SkTypeface> tf, const SkString& text) {
20 return sk_sp<Text>(new Text(std::move(tf), text));
21 }
22
Text(sk_sp<SkTypeface> tf,const SkString & text)23 Text::Text(sk_sp<SkTypeface> tf, const SkString& text)
24 : fTypeface(std::move(tf))
25 , fText(text) {}
26
27 Text::~Text() = default;
28
onRevalidate(InvalidationController *,const SkMatrix &)29 SkRect Text::onRevalidate(InvalidationController*, const SkMatrix&) {
30 // TODO: we could potentially track invals which don't require rebuilding the blob.
31
32 SkPaint font;
33 font.setFlags(fFlags);
34 font.setTypeface(fTypeface);
35 font.setTextSize(fSize);
36 font.setTextScaleX(fScaleX);
37 font.setTextSkewX(fSkewX);
38 font.setTextAlign(fAlign);
39 font.setHinting(fHinting);
40
41 // First, convert to glyphIDs.
42 font.setTextEncoding(SkPaint::kUTF8_TextEncoding);
43 SkSTArray<256, SkGlyphID, true> glyphs;
44 glyphs.reset(font.textToGlyphs(fText.c_str(), fText.size(), nullptr));
45 SkAssertResult(font.textToGlyphs(fText.c_str(), fText.size(), glyphs.begin()) == glyphs.count());
46 font.setTextEncoding(SkPaint::kGlyphID_TextEncoding);
47
48 // Next, build the cached blob.
49 SkTextBlobBuilder builder;
50 const auto& buf = builder.allocRun(font, glyphs.count(), 0, 0, nullptr);
51 if (!buf.glyphs) {
52 fBlob.reset();
53 return SkRect::MakeEmpty();
54 }
55
56 memcpy(buf.glyphs, glyphs.begin(), glyphs.count() * sizeof(SkGlyphID));
57
58 fBlob = builder.make();
59 return fBlob
60 ? fBlob->bounds().makeOffset(fPosition.x(), fPosition.y())
61 : SkRect::MakeEmpty();
62 }
63
onDraw(SkCanvas * canvas,const SkPaint & paint) const64 void Text::onDraw(SkCanvas* canvas, const SkPaint& paint) const {
65 canvas->drawTextBlob(fBlob, fPosition.x(), fPosition.y(), paint);
66 }
67
onAsPath() const68 SkPath Text::onAsPath() const {
69 // TODO
70 return SkPath();
71 }
72
onClip(SkCanvas * canvas,bool antiAlias) const73 void Text::onClip(SkCanvas* canvas, bool antiAlias) const {
74 canvas->clipPath(this->asPath(), antiAlias);
75 }
76
77 } // namespace sksg
78